Basic Chemistry and Macromolecules Flashcards
The nucleus in an atom is made of….
protons and neutrons
Protons and neutrons weigh the same
They each weigh one atomic mass unit (1 amu)
Electrons are found outside the nucleus…
they orbit the nucleus and have no weight
What is an ion?
A charged atom, either positive or negative
Carbon atoms have…
6 protons
Nitrogen atoms have
7 protons
Hydrogen atoms have
1 proton
How do you calculate atomic mass?
Atomic mass = (Protons + Neutrons)
Oxygen atoms have
8 protons
What are the major elements of biological systems?
carbon (C), hydrogen (H), nitrogen (N), oxygen (O), phosphorus (P), and sulfur (S)
What are the trace elements of biological systems?
sodium (Na), potassium (K), chlorine (Cl), manganese (Mn), and Zinc (Zn).
What holds the atoms of molecules together?
Chemical Bonds
What are the three main biological chemical bonds?
covalent bonds, ionic bonds, and hydrogen bonds.
Describe a covalent bond…
Bond between atoms in the same molecule, it is a strong bond due to electron pair sharing
Describe an ionic bond…
Moderately strong bond due to transferring electrons between atoms, creates an attraction
Describe a hydrogen bond…
Weak bond between hydrogen and other electronegative PART of a covalently bonded molecule
What makes atoms want to form a covalent bond?
When it would have to gain or lose several electrons just to fill its shell, it would rather just share them.
What makes atoms want to form an ionic bond?
When it would have to gain or lose just one or two electrons, it would rather just transfer them back and forth.
What makes an atom want to form a hydrogen bond?
This is basically a last resort where none of the other two bonds can be made.
How many electrons are in the first 3 shells of an atom?
1st shell has 2 electrons, 2nd/3rd have eight
Explain Electronegativity…
In a covalent bond, one of the atoms ends up ‘hogging’ more of the electrons’ negative charge even though its supposed to be sharing. This results in the molecule having a slightly negative charge.
What type of bonds are formed between water molecules, and thus give water its properties?
Hydrogen Bonds
How does water (H2O) separate ionic bonds, and thereby dissolve ionic compunds?
Water molecules surround ionic bonds, any negative ions will bond w/ Hydrogen, and positive ions will bond w/ the oxygen.
What is a solution?
Two or more substances joined together to become one uniform substance.
What is responsible for cohesion and therefore the surface tension of water?
Hydrogen Bonds
Give an example of water cohesion and adhesion?
Cohesion - water forming droplets on a surface
Adhesion - water going up a straw or tube
What causes water to be so heat resistant?
Hydrogen Bonds, it requires extra heat energy just to break them first, and then heat the molecules
Why is ice less dense than liquid water?
They hydrogen bonds in ice cannot break, thus causing the molecules to be farther apart
What are the 4 special properties of water
Water is an excellent solvent
Water is cohesive.
Water’s temperature tends to remain stable.
Solid water (ice) is less dense than liquid water.
What is an organic molecule?
Any molecule that contains a carbon to hydrogen (C-H) covalent bond.
What are the 4 major groups of organic bio molecules?
carbohydrates, proteins, nucleic acids, and lipids
What are ‘simple’ carbohydrates?
Carbs made up of only one or two sugar monomers.
What is a ‘complex’ carbohydrate?
Carbs made of made up of more than two sugar monomers covalently bonded together
What is the use of simple carbs?
Quick and fast energy.
What is the use of complex carbs?
Storing energy, cell structure, and signaling
What are lipids?
Another bio macromolecule used for energy but they are hydrophobic.
What are the 4 types of lipids?
- Fats/Oils - long term energy storage
- Phospholipids - cell structure
- Steroids - Hormones, regulates processes
- Waxes - protective water resistant layers
What are proteins?
Most important bio macromolecule made from amino acids.
What are some functions of proteins?
Perform as enzymes to start chemical reactions, DNA, cell transport, molecule transport, receptors, structure
Why can proteins perform so many things?
They are able to form many different structures.
What common features do all organic molecules have?
- They all must contain carbon atoms
- They are covalently bonded to Hydrogen atoms
- They combine to form the major bio macromolecules.
What are the macromolecules’ monomers?
Carbs - Simple Sugars
Proteins - Amino Acids
Nucleic Acids - Nucleotides
Lipids - Fatty Acid Chains
Explain molecularly why oil and water does not mix
Oil is a lipid, and lipids have hydrophobic tails that cause them to keep water away from them
What are nucleotides made of?
A phosphate, a sugar, & a nitrogenous base.
